The EBRI data say that only 18% of Americans are "very confident" about the financial stability of their retirements.

One reason is that U.S. workers have unrealistic expectations about how much money they'll need to retire and live the life they expect. Some 43% say they are targeting saving up to 30% of their annual income on a yearly basis, but that would be too low, according to most financial advisers. The expert estimate: Workers will need to save about two-thirds of their annual income for a comfortable ride through their golden years.

Another 46% of EBRI respondents say they haven't even bothered to calculate how much money they'll need for retirement, and only 2% of workers rate "saving for retirement" as their most important personal financial goal.

Suzanna de Baca, vice president of wealth strategies at Ameriprise Financial reached out and sent along some tips on what Americans can do to improve their confidence in retirement:

Expect the unexpected. The EBRI findings revealed that Americans are pushing back their retirement dates, but that this strategy doesn't always work out the way they might hope. The fact that nearly half of retirees responded they had retired earlier than planned, and 55% of those cited a health problem as the reason they couldn't continue working, illustrates that too often Americans don't get to choose when to stop working. Saving early and often and anticipating there might be bumps in the road (such as an unplanned early retirement) can make all the difference in planning for retirement.

Focus on health care costs. The EBRI data highlight that 29% of workers say they're not at all confident about paying for medical expenses in retirement. That's no surprise, considering all the talk about health care in Washington and rising medical expenses weighing on the minds of baby boomers. But understanding such things as what Medicare covers, the costs associated with long-term care assistance and how family medical history may affect future health care costs and decisions are important steps pre-retirees can take.

Crunch the numbers. About one in four (23%) Americans told EBRI they didn't know what percentage of their income they should save each year to live comfortably in retirement, de Baca says. "We also found in our own Retirement Check-In survey that 38% of pre-retirees (workers age 50 to 70) haven't even estimated what their expenses may be in retirement," she says. "Doing the math can be daunting, but beginning to do so might be more simple than what people anticipate."